### Please describe the problem.

Git's `user.useConfigOnly` is not honored by git-annex commands that create commits (e.g., `init` or `sync`). 

### What steps will reproduce the problem?

Having not globally set `user.{name,email}`, the following will cause git-annex to ignore said setting and proceed with `$USER` as identity:

    $ git config --global user.useConfigOnly true
    $ git init annex && cd $_
    Initialized empty Git repository in /tmp/annex/.git/
    $ git annex init
    init  Author identity unknown
    
    *** Please tell me who you are.
    
    Run
    
      git config --global user.email "you@example.com"
      git config --global user.name "Your Name"
    
    to set your account's default identity.
    Omit --global to set the identity only in this repository.
    
    fatal: no email was given and auto-detection is disabled
    ok
    (recording state in git...)

Looking at the git-annex branch confirms this:

    $ git log git-annex
    commit 8eb575828cf52a3c150780d89c22672a51291f46
    Author: $USER <$USER>
    Date:   2023-03-29 13:22:44 +0200
    
        update
    
    commit 0b247e1da51e742bcf7b027aa25fc0d61520270d
    Author: $USER <$USER>
    Date:   2023-03-29 13:22:44 +0200
    
        branch created

Furthermore, the identity is now even set in the local repository:

    $ git config user.name
    $USER

Enabling `user.useConfigOnly` should prevent this, making it easier to work with several different identities.

### What version of git-annex are you using? On what operating system?

    git-annex version: 10.20230321-gb624394c7
    build flags: Assistant Webapp Pairing Inotify DBus DesktopNotify TorrentParser MagicMime Benchmark Feeds Testsuite S3 WebDAV
    dependency versions: aws-0.24 bloomfilter-2.0.1.0 cryptonite-0.30 DAV-1.3.4 feed-1.3.2.1 ghc-9.0.2 http-client-0.7.13.1 persistent-sqlite-2.13.1.0 torrent-10000.1.3 uuid-1.3.15 yesod-1.6.2.1
    key/value backends: SHA256E SHA256 SHA512E SHA512 SHA224E SHA224 SHA384E SHA384 SHA3_256E SHA3_256 SHA3_512E SHA3_512 SHA3_224E SHA3_224 SHA3_384E SHA3_384 SKEIN256E SKEIN256 SKEIN512E SKEIN512 BLAKE2B256E BLAKE2B256 BLAKE2B512E BLAKE2B512 BLAKE2B160E BLAKE2B160 BLAKE2B224E BLAKE2B224 BLAKE2B384E BLAKE2B384 BLAKE2BP512E BLAKE2BP512 BLAKE2S256E BLAKE2S256 BLAKE2S160E BLAKE2S160 BLAKE2S224E BLAKE2S224 BLAKE2SP256E BLAKE2SP256 BLAKE2SP224E BLAKE2SP224 SHA1E SHA1 MD5E MD5 WORM URL X*
    remote types: git gcrypt p2p S3 bup directory rsync web bittorrent webdav adb tahoe glacier ddar git-lfs httpalso borg hook external
    operating system: linux x86_64
    supported repository versions: 8 9 10
    upgrade supported from repository versions: 0 1 2 3 4 5 6 7 8 9 10
    local repository version: 10

### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)

Yes, it's great!

> [[fixed|done]] --[[Joey]]
